Incandescent lamp and similar device



June 15, 1931 P, CART N 2,084,192

INCANDESCENT LAMP AND SIMILAR DEVICE Filed May 5, 1935 ZNVEN TUE FAT/UL 7. EARTUN.

.M MM

-5 25 A? TURNEY Patented June 15, 1937 UNITED STATES PATENT OFFICE 2,084,192 INCANDESCENT LAMP AND SIMILAR DEVICE Paul O. Cartun, Cleveland Heights, Ohio, assignor to General Electric Company, a corporation of New York Application May 3, 1933, Serial No. 689,189

4 Claims.

o translation element and its supporting structure inside the bulb. Typically, the unitary base structure not only serves as a means for mounting the lamp, but also includes terminals or contacts connected to conductors leading into the bulb through the glass to the translation element inside.

According to my invention, as distinguished from the practice above mentioned, the bulb neck or end is sealed to an end member on which the internal mount of the lamp is mounted independently of the attachment of the bulb. This member or disk is provided with engagement means for mounting the lamp: e. g., the member may form part of a base or terminal device more or less resembling those heretofore used; or such a base may be attached to the member, or united directly thereto; or the disk member itself may be engaged by the securing means of the lamp support. In this way, the member or disk becomes an integral part of the lamp-even, in-

deed, a part of the enclosing envelope itself. The internal mount of the lamp is supported directly by the member or disk, instead of through the medium of the bulb, as heretofore. The current leads need no longer pass through the glass envelope; the usual separate basing operation can be eliminated; and it becomes much easier to locate the translation element accurately and uniformly with reference to the engagement means of the base. This is specially advantageous for lamps used with light projection devices such as reflectors, projectors with lenses, etc; since by accurately locating their sockets or other lamp holding means according to definite standards, standard lamps constructed according to my invention can be efliciently used in them without any necessity or provision for focusing adjustments. Moreover, the lamp is much simpler and stronger, and less expensive to make. Various other features and advantages of the invention will appear from the following description of species thereof, and from the drawing.

In the drawing, Fig. 1 is a perspective view of an illustrative lamp embodying my invention; Fig. 2 is a vertical section through a portion thereof,

illustrating a form of construction representing one species of my invention; Fig. 3 is a similar section illustrating another species; Fig. 4 is a perspective view of another species of lamp; Fig. 5 is a perspective view partly sectioned of a mounting for the lamp shown in Fig. 4; Fig. 6 is a view similar to Fig. 4 of still another species of lamp; and Fig. 7 is a view similar to Fig. 5 of another species of mounting.

II, connected between wires I2 and I3 attached to its ends, and additionally supported, at intermediate points, by wires I4 whose ends are fused into a glass bead I5, itself fused to the wire I3. To increase the rigidity of the supporting structure, a brace wire I6 fused into the bead I5 at one end is welded at its other end to the wire I2. In the present instance, the wires I2, I3 not only support the filament II), but also serve as its current leads. The mount, comprising the filament I 0 and its supporting means just described, is attached directly to a sheet metal diaphragm or disk I1 forming part of (or attached to) a base I 8, and extending across the interior of the base shell I9 at its upper end. The base I8, shown of an Edison or screw type, has a screwthreaded shell I9, serving as one base contact, and has another base contact 20 exposed at its lower end, but insulated from the shell I9. The lower end or neck of the bulb II is sealed directly to the diaphragm or disk I'I. As shown, the base I8 proper (exclusive of the disk I'I) may be the standard Edison base now in general use, consisting of brass screw shell I9 with apertured brass center contact 20 held in place by glass 2| fixed in the inward flanged bottom opening of the shell. The upper end of the shell I9 engages around an outstanding peripheral lip 22 on the circular disk I1, and is attached thereto (by Welding).

As a. matter of manufacturing practice, the disk Il may be separate from the base I8 proper when thebulb I I is sealed to the disk, and the base shell I 9 may afterward be aflixed around the disk. By doing this with the upper edge of the shell I9 flush with that of the disk lip 22, it is easy to locate the base I8 accurately with reference to the filament ID.

The bulb II is preferably made of soft glass, and the diaphragm or disk I I of a metal or alloy (such as an iron alloy containing about 25% of chromium) which has the same thermal co efiicient of expansion as glass, and to which glass is readily scalable. In the sealing operation, the end of the bulb ll may be pressed while hot against the heated disk l1 and thereby also sealed to the inner surface of the lip 22. The lip 22 affords additional adhesion area, but is preferably of such small height (e. g., of a magnitude comparable to the thickness of the glass) that it could not shade or cut oil useful light from the filament Ill.

In mounting the filament supporting structure on the disk H, the wire i2 may be attached by welding it to the disk, and the wire l3 may extend through an opening 23 in the disk, and be embedded and secured in a fused body of glass 24 which closes and seals the opening. The seal 24 may be formed from the residue of a. glass exhaust tube (not shown) sealed to the disk at the opening 23, and sealed ofi (after use) around the wire [3. This may all be done before the base I8 proper is ailixed to the disk H. The portion of the wire 13 embedded in the glass 24 is preferably made of material similar to the disk IT, or such as heretofore used for incandescent lamp leads sealed in glass.

In the construction shown in Fig. 3, the base 25 includes a brass screw shell l9 like that of a standard Edison screw base, and the apertured diaphragm or disk 26 extends across its lower end, being attached (by welding) to the inturned bottom shell flange. Accordingly, the shell l9 surrounds the end or neck of the bulb H. The end of wire I 3 is exposed beyond the seal 24 to serve as a center contact. The disk 26 is shown slightly smaller than the interior of the shell l9, and without any peripheral lip. The shell I9 may be attached to the disk 26 after the latter has been scaled to the bulb l l and the lamp exhausted and sealed at 24, as described above; or, if preferred, the disk 26 may first be attached (welded) to the shell l9 so as to form part thereof, and this composite base shell may afterward be applied and sealed to the bulb neck, and the lamp subsequently exhausted and sealed at 2|. Obviously, the shell l9 and disk 26 of Fig. 3 might be made as one complete bottom shell of the material hereinbefore indicated for the disks l1 and 26.

The lamp shown in Fig. 4 comprises a glass bulb or envelope 21 abutting endwise and sealed against an apertured sheet metal disk 28 which itself forms the terminal device or base of the lamp. This disk 28 has securing wings, ears, or blades 29 formed by integral extensions of the shell metal from the generally circular disk periphery, for engaging suitable mounting means. The internal lamp mount is attached to the disk 26 as in Fig. 3; i. e., the wire 30 is welded to the disk, one of whose wings 29 serves as a base contact, and the wire 3| is secured and insulated in the fused glass tip or spur 32 sealing the disk opening, and projects therefrom as a central bottom contact 33. The disk 28 may be of the ironchromium alloy hereinbefore mentioned.

Fig. shows a mounting device for the lamp of Fig. 4, comprising an insulative base plate 34 with a central socket hole 35 for the base spur 32, spring contact clips 36 for receiving and gripping the disk wings 29, and a spring finger 31 for abutting against the center contact 33. Current supply conductors are connected to one (at least) of the clips 36 and to the finger 31. To mount the lamp in this device, its bottom spur 32 is inserted or pressed home in the hole 35 with the wings 29 intermediate the clips 36, and the lamp is then turned clockwise about the spur 32 as a pivot sufiiciently to force the wings 29 into the clips. which yield resiliently to receive and grip the wings. The wings or blades 29 underlock with the upper portions of the clips 36.

Fig. 6 shows a lamp similar to that of Fig. 4, but with a larger iron-chromium sheet metal disk 40, having its integral peripheral wings or blades 4| retroverted under the disk 40 with clearance between sufiicient to take the upper members of the clips 36 in Fig. 5; so that when the lamp is mounted, the securing means and connections are all concealed under the disk.

Fig. 7 shows another mounting device, with (three) upstanding inward-shouldered spring contact clips 42 amongst which the disks 29 or 40 of Figs. 4 and 6 may be inserted and peripherally engaged. Otherwise, this device is like that of Fig. 5. With this Fig. 7 device. the wings 29 of Fig. 4 would be superfluous, and the wings ll of Fig. 6 would act as mere spacers to augment the effective thickness of the disk with reference to its edge engagement under the clip shoulders.

The iron chromium alloy (hereinbefore referred to) which I prefer is one marketed by the Allegheny Steel Company as "Allegheny 55, of which the following is a typical percentage-byweight analysis:

Iron 67.6 to 71.5 Chromium 26 to 30 Manganese "under..- 1 Nickel do .6 Silicon do .6 Carbon do .25 Sulphur do .025 Phosphorus do .025

The structure shown in Figs. 4-7 is not claimed herein but is described and claimed in my divisional application Serial No. 116,583, filed December 18, 1936.

What I claim as new and desire to secure by Letters Patent of the United States, is,--

1. An electric device comprising a glass bulb or envelope having an opening therein, a base comprising a disk of metal having substantially the same coefiicient of expansion as said glass bulb sealed by fusion directly to the edges of said bulb opening and forming with said bulb a hermetically sealed enclosure, said disk being provided with socket engagement means at its periphery, a filament in said bulb, a pair of leads secured one to each end of said filament, an end of one of said leads being attached to said disk and electrically connected through said disk to said socket engagement means, and the other lead extending through an aperture in said disk, said aperture being sealed by a body of insulating material surrounding said lead.

2. An incandescent electric lamp comprising a glass bulb or envelope having an opening therein, a disk of metal having substantially the same coefficient of expansion as said glass bulb sealed by fusion directly to the edges of said bulb opening and forming with said bulb a hermetically sealed enclosure, a base comprising a metal shell adapted to engage in a socket and secured at one end to said disk and carrying an end contact at its other end insulated from said shell, a filament in said bulb, a pair of leads secured one to each end of said filament, an end of one of said leads being attached to said disk and electrically connected through said disk to said shell, the other lead extending through an aperture in said disk and being electrically connected to said end contact, said aperture in said disk being sealed by a body of insulating material surrounding said lead.

3. Anincandescent electric lamp comprising a glass bulb or envelope having an opening at its 5 end, a disk of metal having substantially the same coefficient of expansion as said glass bulb sealed by fusion directly to the edges of said bulb opening and forming with said bulb a hermetically sealed enclosure, a metal base shell adapted 10 to engage in a socket and surrounding the said end of said bulb and secured at one end to said disk, a filament in said bulb, a pair of leads secured one to each end of said filament, an end of one of said leads being attached to said disk 15 and electrically connected through said disk to said shell, the other lead extending through an aperture in said disk and being exposed at the outer side thereof to serve as an end contact, said aperture in said disk being sealed by a body of insulating material surrounding said lead.

4. An electric device comprising a glass bulb having an opening therein, a base including a metal shell and a disk of metal readily sealable to glass attached to said shell, said disk being sealed directly to the edges of said bulb opening and forming with said bulb a hermetically sealed enclosure, and an energy translation element in said bulb with supporting means therefor at-' tached to said disk independently of said bulb. PAUL O. CAR'I'UN. 

